This invention relates to an apparatus used to support concrete forms of a type that are utilized to mold floors.
Concrete floors of a multi-storied building are often formed by the use of plywood or fiberglass forms that are supported by small beams or purlins, the purlins being supported by shoring apparatus that extends to the ground or to the floor lying below the one being formed. For many years, the shoring has been constructed by utilizing lumber or pipes that were disassembled after each use, moved to a new location, and reassembled. However, considerable time is required to assemble and disassemble such shoring structures. In order to save labor, long frameworks have been constructed which are moved by a heavy crane from one location to another, particularly in constructing the many stories of high rise buildings. Each framework was in the form of a truss with many steel members, the truss having a height such as 8 feet and a length such as 30 feet. While the truss eliminated considerable labor, substantial time was still utilized in positioning the truss at the proper height, particularly where different ceiling heights are utilized in different stories of a building. Also, the trusses were constructed of heavy steel members, not for strength, but to minimize deflection under the heavy loading of poured concrete. Beams of steel were normally utilized rather than a high strength aluminum alloy which may have about the same strength as steel, because aluminum has a much lower modulus of elasticity, and therefore larger deflections could occur which would result in a floor that sagged. If the frameworks could be constructed of lighter weight materials and with fewer members, without decreasing rigidity under heavy loading, then longer frameworks could be utilized because their weight would be low enough to permit movement by available cranes.